Recently, in the field of endoscope, a capsule endoscope having an imaging function and a wireless transmission function has appeared. The capsule endoscope is configured to be swallowed by an examinee as a subject for observation (examination), then, move inside organs (within body cavity) such as stomach and small bowel with the peristaltic motion thereof in an observation period until the endoscope is naturally discharged from the living body of the examinee, and sequentially image using the imaging function.
Further, in the observation period by the movement within these organs, image data imaged within the body cavity by the capsule endoscope is sequentially transmitted to an external device provided outside of the subject by the wireless transmission function such as wireless communication, and accumulated in a memory provided within the external device. The examinee carries the external device having the wireless transmission function and the memory function, and therefore, the examinee is able to act without inconvenience in the observation period after the examinee swallows the capsule endoscope and before discharges it. After observation, a doctor or nurse is able to display images within the body cavity based on the image data accumulated in the memory of the external device on display means such as a display and make diagnoses.
In this type of capsule endoscope, for example, there is one to be swallowed as shown in Patent Document 1. In order to control the driving of the capsule endoscope, a configuration having a reed switch turned on and off by an external magnetic field therein and accommodated in a package including a permanent magnet for supplying the external magnetic field has been proposed. That is, the reed switch within the capsule endoscope has a structure that maintains the off-state under the environment in which a magnetic field having predetermined intensity or more is provided and turns on due to reduction in the intensity of the external magnetic field. Accordingly, in the condition in which the capsule endoscope is accommodated in the package, the capsule endoscope is not driven. When the capsule endoscope is taken out from the package at the time of being swallowed, the capsule endoscope is spaced from the permanent magnet, no longer affected by the magnetic force, and started to be driven. The capsule endoscope has such a configuration, and therefore, the capsule endoscope can be prevented from being driven when it is accommodated within the package, and imaging of images by the imaging function of the capsule endoscope and transmission of image signals by the wireless transmission function are performed after it is taken out from the package.
Patent Document 1: International Publication No. 01/35813 Pamphlet